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If N ₀ is the original mass of the substance of half- life period t _ 1 / 2 =5 years, then the amount of substance left after 15 years is

Options

  1. AN ₀ / 8
  2. BN ₀ / 16
  3. CN ₀ / 2
  4. DN ₀ / 4

Correct answer

A. N ₀ / 8

Step-by-step solution

Amount left =N₀ / 2^n=N₀ / 8 ( Here n=15 / 5=3)

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